Overhaul the documentation

[buehner]

SHOGun2 is growing and a lot of things have changed but it's been a while ago that the documentation/wiki has been updated.

We need to update the documentation to the latest state of development.

The documentation should also contain information about the permission evaluation as desribed here: #182

[marcjansen]

Good reminder, but I fear that even the updated content will be stale soon, as lots of stuff is changing in SHOGun (we aren't very new a stable release, are we?).

Nonetheless we also need prose docs… we can possibly try to update them more regularly?!?

[marcjansen]

Is the wiki still OK? I fear it isn't.

[ahennr]

In this context the JavaDoc comments of methods and fields should be revised as well (e.g. in importer, see #285) .

[gabriel-lucas]

Hi,

First I want to thank you for developing this interesting project I am interested in Shogun and just tried to make it run. I followed the documentation in here: https://github.com/terrestris/shogun-legacy. but I had no luck obtaining the war file.

I would appreciate much if the documentation could be improved.